Winning is not done in short sprints, but rather long endurance challenges.
Forget about slipping out of your shoes because of loose laces or feeling pressure from too-tight tying when doing those sprints.
A satisfying career, to extend the tiresome metaphor, is less a marathon than a series of sprints.
Over the past six months, I have slowly built up to about 20 minutes of sauna after doing 30 minutes of sprints twice a week.
As your stamina improves, your 'sprints' can be faster or done up hills to intensify the workout.
When I was doing hill sprints to prepare for my ski racing - my heart and lungs and leg muscles all on fire - I'd often be hit by the sensation that there were no resources left inside me with which to keep going.
